Binuclear iron phthalocyanine/reduced graphene oxide(bi-Fe Pc/RGO) nanocomposite with good electrocatalytic activity for ORR in alkaline medium was prepared in one step. High angle annular dark field image scanning tr...Binuclear iron phthalocyanine/reduced graphene oxide(bi-Fe Pc/RGO) nanocomposite with good electrocatalytic activity for ORR in alkaline medium was prepared in one step. High angle annular dark field image scanning transmission electron microscopy(HAADF-STEM) and energy dispersive X-ray spectroscopy element mapping results show bi-Fe Pc was uniformly distributed on RGO. An obvious cathodic peak located at about-0.23 V(vs. SCE) in CV and an onset potential of-0.004 V(vs. SCE) in LSV indicate the as-prepared bi-Fe Pc/RGO nanocomposite possesses high activity which is closed to Pt/C for ORR. The ORR on bi-Fe Pc/RGO nanocomposite follows four-electron transfer pathway in alkaline medium. Compared with Pt/C, there is only a slight decrease(about 0.02 V vs. SCE) for bi-Fe Pc/RGO nanocomposite when the methanol exists. The excellent activity and methanol tolerance in alkaline solutions proves that bi-Fe Pc/RGO nanocomposite could be considered as a promising cathode catalyst for alkaline fuel cells.展开更多
Four μ-2-chloroterephthalato binuclear iron(Ⅱ) complexes, namely [Fe2 (CTPHA) L4]-(ClO4)2, where L stands for 4,4'-dimethyl-2,2'-bipyridine (Me2-bpy); 2,9-dimethyl-l, 10-phenanthro-line (Me2-phen); 5-chloro-...Four μ-2-chloroterephthalato binuclear iron(Ⅱ) complexes, namely [Fe2 (CTPHA) L4]-(ClO4)2, where L stands for 4,4'-dimethyl-2,2'-bipyridine (Me2-bpy); 2,9-dimethyl-l, 10-phenanthro-line (Me2-phen); 5-chloro-l, 10-phenanthroline (Cl-phen); 4, 7-diphenyl-l, 10-phenanthroline (Ph2-phen), respectively, and CTPHA represents 2-chlorolerephthalate dianion, have been synthesized and characterized. Based on the elemental analyses, molar conductance measurements and spectroscopic studies, extended CTPHA-bridged structures consisting of two iron(Ⅱ) ions, each in a distorted octahedral environment, are proposed for these complexes. [Fe2 CTPHA)-(Me2-bpy)4] (ClO2 (1) and [Fe2(CT-PHA)·(Me2-phen)4](ClO4)2 (2) complexes were characterized by variable temperature magnetic susceptibility (4-300 K) measurements and the observed data were successfully simulated by the equation based on the spin Hamiltonian operator, H = - 2JS1 · S2 , giving the exchange integrals J = - 1.28 cm-1 for 1 and J = - 1.85 cm-1 for 2. These results indicate the presence of a weak antiferromagnetic spin-exchange interaction between the metal ions within each molecule.展开更多
The first binuclear iron fullerene derivative of(η 2 C 60 )[Fe(CO) 2(C 5H 5)] 2 , which was yellow brown and sensitive to air and moisture, was prepared by the reaction of trans [Fe(CO) 2(C 5H 5)] 2 with C 60 in benz...The first binuclear iron fullerene derivative of(η 2 C 60 )[Fe(CO) 2(C 5H 5)] 2 , which was yellow brown and sensitive to air and moisture, was prepared by the reaction of trans [Fe(CO) 2(C 5H 5)] 2 with C 60 in benzene under an atmosphere of dried nitrogen using conventional Schlenk techniques and has been characterized by using elementary analysis and IR, 1H NMR, 13 C NMR and XPS spectra. The infrared spectrum of the title compound indicates the disappearance of ν CO at 1 760 cm -1 for bridge carbonyl and the appearance of the only terminal CO lying at a higher wave number than that of the starting material, which reveals the electron deficient behavior of C 60 . And the important 1H, 13 C NMR chemical shift and XPS of trans [Fe(CO) 2(C 5H 5)] 2 , C 60 and its novel complex along with their relative assignments are briefly discussed.展开更多
基金supported by the National Natural Science Foundation of China (21275014, 21375005)the Excellent Young Scientists Fund of NSFC (21322501)+2 种基金the Importation and Development of High-Caliber Talents Project of Beijing Municipal Institutions (CIT& TCD20140309)the Program for New Century Excellent Talents in University (NCET-12-0603)the Beijing Natural Science Foundation Program and Scientific Research Key Program of the Beijing Municipal Commission of Education (KZ201310005001)
文摘Binuclear iron phthalocyanine/reduced graphene oxide(bi-Fe Pc/RGO) nanocomposite with good electrocatalytic activity for ORR in alkaline medium was prepared in one step. High angle annular dark field image scanning transmission electron microscopy(HAADF-STEM) and energy dispersive X-ray spectroscopy element mapping results show bi-Fe Pc was uniformly distributed on RGO. An obvious cathodic peak located at about-0.23 V(vs. SCE) in CV and an onset potential of-0.004 V(vs. SCE) in LSV indicate the as-prepared bi-Fe Pc/RGO nanocomposite possesses high activity which is closed to Pt/C for ORR. The ORR on bi-Fe Pc/RGO nanocomposite follows four-electron transfer pathway in alkaline medium. Compared with Pt/C, there is only a slight decrease(about 0.02 V vs. SCE) for bi-Fe Pc/RGO nanocomposite when the methanol exists. The excellent activity and methanol tolerance in alkaline solutions proves that bi-Fe Pc/RGO nanocomposite could be considered as a promising cathode catalyst for alkaline fuel cells.
基金Natural Science Foundation of Shandong Province (No. Y97-D17076)National Natural Science Foundation of China (No. 29631040).
文摘Four μ-2-chloroterephthalato binuclear iron(Ⅱ) complexes, namely [Fe2 (CTPHA) L4]-(ClO4)2, where L stands for 4,4'-dimethyl-2,2'-bipyridine (Me2-bpy); 2,9-dimethyl-l, 10-phenanthro-line (Me2-phen); 5-chloro-l, 10-phenanthroline (Cl-phen); 4, 7-diphenyl-l, 10-phenanthroline (Ph2-phen), respectively, and CTPHA represents 2-chlorolerephthalate dianion, have been synthesized and characterized. Based on the elemental analyses, molar conductance measurements and spectroscopic studies, extended CTPHA-bridged structures consisting of two iron(Ⅱ) ions, each in a distorted octahedral environment, are proposed for these complexes. [Fe2 CTPHA)-(Me2-bpy)4] (ClO2 (1) and [Fe2(CT-PHA)·(Me2-phen)4](ClO4)2 (2) complexes were characterized by variable temperature magnetic susceptibility (4-300 K) measurements and the observed data were successfully simulated by the equation based on the spin Hamiltonian operator, H = - 2JS1 · S2 , giving the exchange integrals J = - 1.28 cm-1 for 1 and J = - 1.85 cm-1 for 2. These results indicate the presence of a weak antiferromagnetic spin-exchange interaction between the metal ions within each molecule.
文摘The first binuclear iron fullerene derivative of(η 2 C 60 )[Fe(CO) 2(C 5H 5)] 2 , which was yellow brown and sensitive to air and moisture, was prepared by the reaction of trans [Fe(CO) 2(C 5H 5)] 2 with C 60 in benzene under an atmosphere of dried nitrogen using conventional Schlenk techniques and has been characterized by using elementary analysis and IR, 1H NMR, 13 C NMR and XPS spectra. The infrared spectrum of the title compound indicates the disappearance of ν CO at 1 760 cm -1 for bridge carbonyl and the appearance of the only terminal CO lying at a higher wave number than that of the starting material, which reveals the electron deficient behavior of C 60 . And the important 1H, 13 C NMR chemical shift and XPS of trans [Fe(CO) 2(C 5H 5)] 2 , C 60 and its novel complex along with their relative assignments are briefly discussed.